Russia on Friday handed an unusually lenient three-year suspended sentence to a student convicted of making calls for extremism on a video blog condemning President Vladimir Putin.

Yegor Zhukov, a 21-year-old student at Moscow's prestigious Higher School of Economics, was charged over his YouTube videos, which have had hundreds of thousands of views.

His conviction by a Moscow court now prevents him from blogging for two years and means he is on a list of "extremists."

Nevertheless the sentence by judge Svetlana Ukhnaleva was unexpectedly mild after prosecutors had asked for a four-year jail term.

Young Russian opposition supporters have been jailed for up to four years for participating in a July street protest in Moscow against Putin.

Zhukov, a politics student, was arrested in the summer over a protest called by opposition leader Alexei Navalny, but then released under house arrest and charged with making online calls for extremism.

Fellow students and teachers at his university as well as a popular rapper, Oxxxymiron, regularly attended hearings in his case.

After the sentencing, hundreds of supporters outside the court chanted: "A suspended sentence is still a sentence!" and "Acquit him!"

Zhukov's lawyer Murad Musayev told journalists: "This cannot be seen as a complete victory because the guy is innocent."

Navalny wrote on Twitter that Russia "knowingly charged an innocent man."

Deputy rector of the Higher School of Economics Valeriya Kasamara said the court's two-year ban on managing Internet sites means "he has no limits on Internet access, he is restricted only from blogging."

"From Monday, he is a student," she confirmed, while he will need to check in regularly with police.

Nevertheless Kasamara, who burst into tears after the verdict, said she disagreed with the sentence because "Yegor is not an extremist."

Russian student and blogger Yegor Zhukov is surrounded by supporters outside Moscow's Kuntsevsky district court after getting his suspended sentence
Russian student and blogger Yegor Zhukov is surrounded by supporters outside Moscow's Kuntsevsky district court after getting his suspended sentence AFP / Kirill KUDRYAVTSEV

Kremlin spokesman Dmitry Peskov gave an ambivalent response, saying: "We're against turning a blind eye to something but are also not keen on exaggerating things."

Zhukov emerged from court and raised a hand in triumph as supporters shouted "Yegor!" Police had to close one lane of a nearby road due to the size of the crowd.

"This isn't complete victory all the same, although I'm very glad to be free," he said.

"This is all politics. They have turned courts into a repressive institution. We must fight this," he said, thanking supporters for highlighting his case.

"The fact that I'm here and this is happening is all thanks to you," he said.

"This shows that attracting attention to such things really works," said rapper Oxxxymiron.

"Yegor got a lot of support compared to other defendants in the (protest) case, possibly this influenced the softening of the sentence," said Gleb, a 21-year-old student.

The son of a former cosmonaut-in-training, Zhukov has won praise for his eloquence and Novaya Gazeta opposition newspaper published his final statement in court, made on Wednesday, in full.

In his speech, he argued that Russian authorities deliberately crush any initiative and create an atomised society where no one is prepared to take any responsibility.

"I'm glad I got this chance to go through an ordeal in the name of values that are dear to me," he said.

In another unusually mild verdict on Friday, Pavel Novikov, 32, accused of hitting a policeman with a bottle of water at a July protest, was released and fined 120,000 rubles ($1,883), while another, Vladimir Yemelyanov, received a two-year suspended sentence, Mediazona website reported.

Another protester, Nikita Chirtsov, was sentenced to one year in prison for pushing a policeman.